1. Technical Field of the Invention
The present invention relates to an integrated building production information system capable of making the work solution of a design department and an execution department more rational and more efficient by electronicizing key jobs (integration, estimation, procurement, profit-and-loss management and the like) of the production side in a field of construction.
2. Background Art
Particularly, the present invention relates to a database CAD (computer-aided design) system which can aim at making more efficient and more laborsaving the work of preparing design drawings and specifications and at improving the productivity and quality by making it possible for personal computers using CAD software connected with a database to grasp necessary quantities and share necessary data for design among the personal computers, by integrating specifications and quantities in a design work using CAD's performed by each personal computer, and by unifying the data flow from design information to estimation and execution information.
Up to now, pattern information (drawing information) as information for building production has been generally communicated by means of “paper”.
On the contrary, in recent years, with the advance of information-systematization in each domain of building production, CAD is extensively used and the present purpose of it is to improve the efficiency of drawing figures and the quality of drawing representation.
Thus, due to the above-mentioned purpose, the range of utilization of CAD stays mostly within each domain specific to design or execution.
From 1980's to the early part of 1990's, “CAD systems for integrating design and execution into a consistent work” were developed by many companies including general constructors, and features common to them are as follows.    (1) A minicomputer or an EWS (engineering workstation) is utilized as a base;    (2) Attribute parameters are made separately by the respective companies;    (3) Jobs of picking and totalizing quantities are performed within a single system;    (4) Mainly the scope of utilization of the system is on and after an execution design stage; and    (5) The system is operated by an operator.
However, for all CAD data of drawings made with much effort, there has not been a mechanism for utilizing them in a process of estimating quantities or preparing execution drawings being the next process.
Estimated quantities have been computed mainly by an outside order estimation office on the basis of design drawings (paper information), and execution drawings have also been made mainly by an outside order office as definitely settling pending parts in design drawings and adding information of execution to them.
On the other hand, execution design drawings and specifications representing the contents of estimation and contract have contained a too small amount of information and a too large amount of pending contents to perform execution as they are.
The present situation in which redo or readjustment occurs due to defining the contents of design or specifications as preparing execution drawings in course of construction and the next process is performed as the execution information is not definitely determined. Such present situation has hindered the rationalization in various aspects.
In order to promote the rationalization of building production, it is necessary to make the degree of definite settlement as high as possible at an upstream stage, namely, at a design stage in an early process.
And the maximum usefulness of electronic information including CAD data is clearly the possibility of using the data in various applications, and in order to improve the efficiency of building production by making the best use of its property, it is necessary to distribute design information generated at an early stage of a project as converting the design information so as to meet each stage of production.
Thereupon, there is a synthetic drawing preparation system of Japanese Patent Laid-Open Publication No. Hei 8-235,243 of a Japanese patent application among matters filed as a synthetic drawing preparation system making it possible to uniformly handle building drawing data and equipment drawing data prepared by heterogeneous CAD apparatuses.
This is a synthetic drawing preparation system which converts drawing data among a building CAD apparatus for preparing building drawings, an equipment CAD apparatus for preparing equipment drawings and a synthetic CAD apparatus for preparing synthetic drawings, said system converting drawing data on the layer of the building CAD apparatus or equipment CAD apparatus and drawing data on the layer of the synthetic CAD apparatus into each other, and preparing synthetic drawings by means of the synthetic CAD apparatus on the basis of drawings prepared by the building CAD apparatus and the equipment CAD apparatus.
According to this Japanese Patent Laid-Open Publication No. Hei 8-235,243, drawings of the building side such as plan detail drawings, skeleton drawings and the like to be prepared by building CAD apparatuses are made by the respective building CAD apparatuses.
Since the prepared drawings have the data formats of the respective dedicated CAD apparatuses, they are converted into the DXF format and converted from each unique layer of these dedicated CAD apparatuses into the layer of the synthetic CAD apparatus.
And each of drawings to be prepared by the equipment side such as drawings of electric equipment, sanitary equipment, air conditioning equipment and the like is made by a CAD apparatus possessed by each subcontractor in charge of equipment.
Since the prepared drawings have the data formats of the respective dedicated CAD apparatuses, they are converted into the DXF format and converted from each unique layer of these dedicated CAD apparatuses into the layer of the synthetic CAD apparatus.
A processing synthetic CAD apparatus in a synthetic CAD apparatus can handle uniformly drawings made by a building CAD apparatus or an equipment CAD apparatus. In case that a building side performs a change having an influence on the whole execution, for example, a synthetic CAD apparatus converts the data format and layer of a changed drawing and passes the converted drawing data to another building CAD apparatus or equipment CAD apparatus, which can perform a necessary change on the basis of the changed drawing data by means of each dedicated CAD. The changed drawing is converted in the synthetic CAD apparatus side and is combined with a layer according to a synthetic drawing and outputted to a display device or a plotter.
In this way, since a drawing made by each dedicated CAD apparatus can be handled by another dedicated CAD apparatus, a modification based on some changed spot can be handled uniformly by a building side or an equipment side and, therefore, even a large-scale building can be corrected exactly and quickly.
However, said synthetic drawing preparation system of Japanese Patent Laid-Open Publication No. Hei 8-235,243 is a system for securing the compatibility in a job of making a synthetic drawing at an execution stage but is not a system for securing the compatibility at a design stage. Securing the compatibility at an execution stage results in having many pending matters, and redo and readjustment occur even in the course of execution as described above and the rationalization is hindered in various aspects by entering the next process as leaving necessary information not definitely determined.
And this system uses pattern data of a drawing but does not inheritably use the attribute of a design drawing. The linkage of such pattern data is low in the degree of freedom and the CAD data of a design drawing can be utilized in making a synthetic drawing in the next process as pattern data, but since the attribute of it is not utilized, the data cannot be utilized in calculation of quantities to be estimated.
Further, said synthetic drawing preparation system of Japanese Patent Laid-Open Publication No. Hei 8-235,243 is a system which fully performs a layer management of drawing data and converts the layer of drawing data into a layer configuration convenient for a synthetic drawing on the basis of a predetermined rule of layer conversion, but the layer rule is not often strictly observed and an effective result cannot be often obtained. Generally, management based on layer is effective for an object but is often ineffective for another object, and in case of using a layer management for another object, such a system performs conversion but often cannot effectively distribute data.
Further, the synthetic drawing preparation system of Japanese Patent Laid-Open Publication No. Hei 8-235,243 is supposed as a system primarily handling two-dimensional matters and cannot perform examination from an optional direction in confirming the compatibility and is difficult to estimate exactly the quantities.
By the way, in order to integrate building production information, it is necessary to take the compatibility among building information, structure information and equipment information, but it is caused by the following reasons that CAD systems of building, structure and equipment have not been unified and have not come to spread. There are such reasons as a fact that a CAD system has been expensive in lease expense of hardware/software, maintenance cost and the like, a fact that there has not been a receiver of data since CAD has not been popular in building sites, a fact that estimation is often performed by manually picking up and no electronic data have been utilized in a downstream process, and a fact that an operator has been required not only to operate a CAD system but also to have deep knowledge of both design drawings and execution drawings, namely, a young operator skilled in operation of CAD has also needed to be skilled in settlement or sequence of execution and the like.
Further, the following factors are conceivable.
The work of a conventional CAD system is only the exchange of pattern data in the DWG format or DXF format and exchanges data having no attribute from beginning to end.
And two-dimensional data are primarily handled and the correction of errors caused by conversion requires much time, and it is difficult to check the compatibility by means of two-dimensional superposition of pattern data.